#include <bits/stdc++.h>
#define int long long
using namespace std;
const int maxn = 3005;
char s[maxn][maxn];
int vis1[maxn][maxn], vis2[maxn][maxn], vis3[maxn][maxn], n, m, cnt, rot[maxn][maxn], ans;
bool visS[maxn][maxn], visT[maxn][maxn];
vector<pair<int, int>> vec;
bool check(int x, int y) {
	return (x >= 1 && x <= n && y >= 1 && y <= m && s[x][y] == '.');
}
void dfs1(int x, int y) {
	visS[x][y] = 1;
	if(x == n && y == m) return;
	if(check(x + 1, y) && !vis1[x + 1][y]) {
		vis1[x + 1][y] = 1;
		dfs1(x + 1, y); 
	}
	if(check(x, y + 1) && !vis1[x][y + 1]) {
		vis1[x][y + 1] = 2;
		dfs1(x, y + 1);
	}
}
void dfs2(int x, int y) {
	visT[x][y] = 1;
	if(x == 1 && y == 1) return;
	if(check(x, y - 1) && !vis2[x][y - 1]) {
		vis2[x][y - 1] = 2;
		dfs2(x, y - 1);
	}
	if(check(x - 1, y) && !vis2[x - 1][y]) {
		vis2[x - 1][y] = 1;
		dfs2(x - 1, y);
	}
}
void dfs3(int x, int y) {
	if(x == n && y == m) return;
	if(check(x, y + 1) && !vis3[x][y + 1]) {
		vis3[x][y + 1] = 2;
		dfs3(x, y + 1);
	}
	if(check(x + 1, y) && !vis3[x + 1][y]) {
		vis3[x + 1][y] = 1;
		dfs3(x + 1, y); 
	}
	
}
signed main() {
	ios::sync_with_stdio(0);
	cin.tie(0), cout.tie(0);
	cin >> n >> m;
	for(int i = 1;i <= n;i++) {
		cin >> s[i] + 1;
		for(int j = 1;j <= m;j++) cnt += (s[i][j] == '.');
	}
	if(n == 1 && m == 1) {
		cout << 0;
		return 0;
	}
	dfs1(1, 1);
	if(!visS[n][m]) {
		cout << cnt * (cnt - 1) / 2 << '\n';
		return 0;
	}
	dfs2(n, m);
	dfs3(1, 1);
	int X = n, Y = m, res = 1;
	while(!(X == 1 && Y == 1)) {
		rot[X][Y] = 1;
		if(vis3[X][Y] == 1) X --;
		else Y --;
	}
	X = n, Y = m;
	while(!(X == 1 && Y == 1)) {
		vec.push_back(make_pair(X, Y));
		res += rot[X][Y];
		if(vis1[X][Y] == 1) X --;
		else Y --;
	}
	vec.push_back(make_pair(1, 1));
	ans = res * (cnt - res) + res * (res - 1) / 2;
	for(pair<int, int> t : vec) {
		int X = t.first, Y = t.second, resN = 0;
		X --, Y ++;
		while(X >= 1 && Y <= m) {
			if(visS[X][Y] && visT[X][Y]) break;
			X --, Y ++;
		}
		if(!(X >= 1 && Y <= m)) continue;
		int XX = X, YY = Y;
		while(!(XX == 1 && YY == 1)) {
			resN += rot[XX][YY];
			if(vis1[XX][YY] == 1) XX --;
			else YY --;
		}
		XX = X, YY = Y;
		if(vis2[XX][YY] == 1) XX ++;
		else YY ++;
		while(!(XX == n && YY == m)) {
			resN += rot[XX][YY];
			if(vis2[XX][YY] == 1) XX ++;
			else YY ++;
		}
//		cout << X << " " << Y << " " << resN << " " << res << '\n';
		ans += resN + 2 - res;
	}
	cout << ans << '\n';
}